New and Old TSPO PET Radioligands for Imaging Brain Microglial Activation in Neurodegenerative Disease

  • Laura Best
  • Christine GhaderyEmail author
  • Nicola Pavese
  • Yen Foung Tai
  • Antonio P. Strafella
Neuroimaging (N. Pavese, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Neuroimaging


Purpose of Review

We will discuss the developments in TSPO PET imaging and the contribution this technique has had to understanding neuroinflammation in vivo, as well as the limitations inherent to the currently available radioligands and the potential future direction.

Recent Findings

Positron emission tomography (PET) imaging targeting the translocator protein 18 kDa (TSPO) has led to major advances in understanding the pathological role played by microglia activation and neuroinflammation in a diverse range of neurodegenerative conditions.


The first-generation radioligand 11[C](R)-PK11195 has been the most widely studied and has led to considerable advancements in defining the role of neuroinflammation in neuronal degeneration and dysfunction. However, limitations including low signal-to-noise ratio and high nonspecific binding have led to the development of new TSPO-specific radioligands in an attempt to improve the quality of TSPO imaging. Unfortunately, these new radioligands have not been without their own problems, and the expected improvement in image quality has not been achieved.


Neuroinflammation Microglial activation TSPO PET Neurodegenerative diseases 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Laura Best
    • 1
  • Christine Ghadery
    • 2
    Email author
  • Nicola Pavese
    • 1
  • Yen Foung Tai
    • 3
  • Antonio P. Strafella
    • 2
  1. 1.Clinical Ageing Research UnitNewcastle University, Campus for Ageing and VitalityNewcastle Upon TyneUK
  2. 2.The Edmond J. Safra Program in Parkinson’s Disease & Movement Disorder Unit, Toronto Western Hospital & Krembil Research Institute, University Health Network; Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental HealthUniversity of TorontoTorontoCanada
  3. 3.Imperial College London, South Kensington CampusLondonUK

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